I have studied applied math and got a phdPhD (3yrs) in that field with applications in fluid dynamics. Then in my first postdoc (1.5yrs) I did again a postdoc in applied math but studied applications in biological modeling. Now in my second postdoc (started 2 months ago) I am studying a new application, avalanches. The unifying theme is supposed to be the modeling. My problem is that I am feeling a bit lost, feeling like I have to start again from the beginning in this field (methods, codes et.c). I am completely lost and even if I try to make myself see that as a challenge, I am thinking that I want to go and study computational cosmology but then in this way I will never be enough successful for academia. This is because no ones wants someone that knows a little bit of everything but is expert in nothing. There are other things that I like as topics but not my current postdoc ( I actually got it only because I could not find another position on time to leave the first postodoc postdoc). Can you please give me some advice? I would really appreciate it, since I am feeling lost for too long now.